The effects of blood lactate levels on postoperative morbitis and mortality in case over 3 HOURS in itracranial surgery

Purpose: The aim of this study is to determine the importance of serum lactate levels in the management of craniotomy patients. Materials and Methods: After obtaining ethical approval, this study was conducted between 01.11.2022-01.04.2023. Data from 50 adult patients aged 18-75 years in ASA I-II-III groups, who underwent craniotomy surgery lasting more than 3 hours in Dicle University Hospital, were collected and analyzed after obtaining verbal and written consent from the patients. Results: Our study included a total of 50 patients with a mean age of 43.06 ±15.8, 58% (n=29) of whom were female. According to the preoperative anesthesia risk status of the patients, ASA 1 was found in 8%, ASA 2 in 74%, and ASA 3 in 18% of the patients. At least one comorbid disease was found in 42% (n=21) of the patients, with hypertension being the most commonly identified comorbidity. 84% (n=42) of the patients were operated on due to intracranial mass. In our study, approximately 85% of the patients had intracranial masses, with an average surgical time of 305 minutes and average anesthesia time of 334 minutes. The average fluid volume administered was recorded as 756 ml, with 6 patients receiving erythrocyte (ES) suspension once and 5 patients receiving it twice. The lactate value measured in the first postoperative hour was 2.2±1.3, and the lactate value in the postoperative 24th hour was 1.8±1.2. 92% (n=46) of the patients had a GCS score of 15 in the postoperative 24th hour. Total mortality was found to be 4% (n=2). No correlation was found between intraoperative lactate levels and surgical time during the start, 2nd, 4th, and 6th hours, while a positive correlation was found between lactate at the 8th hour. The correlation between surgical time and lactate levels became stronger with the increase in time, and the strongest correlation was found between the 4th and 6th hour lactate values. The average lactate value at the start of the operation was 1.576, which increased with time. No correlation was found between BMI and any lactate level. The mean anesthesia time was 349.09 minutes with a standard deviation of 73.80 minutes in the group with morbidity (n=33), while it was 307.06 minutes with a standard deviation of 69.98 minutes in the group without morbidity (n=17) (P=0.046). Similarly, the mean surgical time was 320.00 minutes with a standard deviation of 72.59 minutes in the group with morbidity, while it was 277.06 minutes with a standard deviation of 69.98 minutes in the group without morbidity (P=0.041). There was no significant difference between the two groups in terms of age, weight, and BMI. The p-value was calculated as 0.943 for age, 0.264 for weight, and 0.534 for BMI. No significant differences were found between the groups in terms of lactate values, ASA scores, comorbidity, etc. When the relationship between anesthesia time and morbidity was examined by ROC analysis, sensitivity was found to be 49% and specificity was 83% when the cut-off value was 330. The AUC (area under the curve) was found to be 67% (95% CI: 0.503-0.827) at this cut-off value. Conclusions: According to the current literature and the findings of this study, increasing surgical time is associated with elevated intraoperative and postoperative lactate levels. These rising lactate levels may lead to increased morbidity and mortality.